Buckle



FIG. 1 is a perspective view of a buckle from the front, plan, and right side showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a plan view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a right side view thereof, a left side view being symmetrical to the right side view; and,

FIG. 7 is a cross-sectional view of line 7-7 in FIG. 2.

The broken lines depict portions of the buckle that form no part of the claimed design. 

The ornamental design for a buckle, as shown and described. 